Something

%titles = {};
sub add;
add "foo";
add "bar";
add "bar";
sub add
{
my $t = $_[0];
my $k=$t;
my $seq=1;
while (exists($titles{$k})) {
$k=$t..$seq;
$seq+=1;
}
$titles{$k}=1;
print "added $k\n";
}